1. Field of the Invention
The present invention relates to energy management and, more particularly to an energy accumulator system used in conjunction with cold or heat sources.
2. Background Art
The ever-increasing costs of energy are associated with numerous factors: increasing energy demand for full capacity supply, diminishing stocks of fossil fuel, volatility of the supply capacity in view of political, geographical and meteorological factors. Therefore, energy management has rapidly evolved to minimize the impact of high energy costs, and cost variations.
It is known to use liquid as a storage medium for energy. For instance, heating systems using water circuits to transfer heat from a central heat source, such as a furnace, to peripheral radiators, in various rooms of the building. Water accumulates heat at the heat source, and releases heat at the radiators.
Liquids have also been used to store cold heat. Ice banks have been developed to store cold heat, for instance at periods of the day when energy costs are lower (e.g., at night). The stored cold heat is then used to fill refrigeration and/or air conditioning needs.
Some products have been used to enhance the storage capacity of the liquids. For instance, alcohols, such as glycol, have been used to change the melting point of the accumulator fluid, so as to store cold latent heat.
Such energy accumulator systems take into account the energy prices as a function of the period of the day. However, other factors should be considered in order to minimize the energy consumption, such as efficiency of operation of the heat or cooling sources.